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A072038
Column of Zorach additive triangle in which n appears (or 0 in the unlikely event that it does not).
4
1, 1, 2, 1, 1, 2, 1, 1, 3, 1, 2, 2, 2, 1, 1, 1, 3, 2, 1, 1, 1, 1, 3, 2, 3, 4, 1, 1, 2, 1, 3, 1, 1, 2, 2, 2, 1, 1, 1, 4, 2, 3, 2, 1, 1, 1, 1, 4, 2, 1, 1, 1, 3, 1, 1, 4, 2, 2, 1, 1, 2, 1, 3, 1, 2, 5, 1, 1, 3, 2, 3, 1, 4, 1, 2, 2, 3, 1, 1, 1, 1, 1, 2, 3, 1, 1, 1, 5, 2, 1, 1, 3, 2, 1, 4, 2, 2, 1, 1, 1, 2, 1, 1, 5, 1
OFFSET
1,3
FORMULA
If a(n) > 0: n = A035312(A072039(n)-1, a(n)-1).
EXAMPLE
a(8)=1 since 8 appears in the first (i.e. left hand) column.
PROG
(Haskell) -- See link.
CROSSREFS
If a(n)=1 then n is in A035311, if a(n)=A072039(n) then n is in A035313. Cf. A035312, A035358, A072039.
Sequence in context: A281681 A218799 A078770 * A284315 A262928 A228429
KEYWORD
nonn
AUTHOR
Henry Bottomley, Jun 07 2002
STATUS
approved